Alright, so you know who the basics are, but here, I'll give you all the characters in the game (well, those you see more than once and are semi-important, not those people you meet in the slums)

First off, the mainest main character of them all... Cloud Strife

Name: Cloud Strife
Age: 21
Gender: Male
Weapon: Sword
Background info: The main character of Final Fantasy VII, Cloud grew up with Tifa in Nibelheim. He aspired to become a member of the elite Shinra group of Soldier and be just like Sephiroth. He failed in his mission and met Zack. Him and Zack were with each other for a while, going through many hardships until they got to Midgar. He then joined a group called Avalanche who rebelled against Shinra. His rival is Sephiroth and his main goal is to destroy him. He holds a giant blade at all times and is strong enough to be able to swiftly move the blade.

Name: Barret Wallace
Age: 35
Gender: Male
Weapon: Gun arm
Background info: Barret was born and raised in the mining village of Corel. When Shinra wanted to build a reactor there, the people refused but had to accept. When Shinra believed that the people were abusing the reactor, they set out for destruction. Barret lost his right arm in a skirmish with Shinra troops and after that, he had a gun put on the arm for his revenge on Shinra and started a group called Avalanche which was hell bent on destroying Shinra. Also has a daughter named Marlene.

Name: Tifa Lockhart
Age: 20
Gender: Female
Weapon: Martial Arts
Background info: Tifa grew up with Cloud, they were close at times, but a lot of other boys were around her most of the time so they could never really get together. After Cloud left, Tifa became really sad and eventually left Nibelheim to go the Midgar. There she joined the group Avalanche and started up a bar called 7th Heaven in Sector 7.

Name: Aeris (Aerith) Gainsborough
Age: 22
Gender: Female
Weapon: Striking Staff
Background info: A flower girl in the slums. Aeris was born secretly in the Icicle Village and was soon taken by Shinra to Midgar. Her and her mother escaped to the Sector 5 slums. There, Aeris lives with Elmyra in her house. The Turks kept trying to capture her as she was the last of the Cetra race and valuable to Shinra, but she kept eluding them. She is the best magic user in the game.

Name: Red XIII (Nanaki)
Age: 48
Gender: Male
Weapon: Claws and Teeth
Background info: Actually a teenager still in his years, Red XIII grew up protecting Cosmo Canyon and believing his father was a traitor. He got captured by Shinra and became a research specimen. He was eventually saved by Cloud and the group and also found the truth about his father. His grandfather, Bugenhagen, is human, which makes no sense but who's to argue.

Name: Cait Sith
Age: ?
Gender: Male
Weapon: Megaphone and Dice
Background info: Cait Sith was a fortuneteller in Gold Saucer when it met Cloud and the group. Reeve, Shinra's Head of Urban Development, created it to spy of Cloud and the group. It eventually earned it's keep and became a permanent member of the group, though quite useless

Name: Cid Highwind
Age: 32
Gender: Male
Weapon: Spear
Background info: Cid was going to be the first man in space on Shinra's No. 26 rocket. When Shera screwed up his rocket plan, she decided to let Cid live with her in Rocket Town. Cid is a tense man who swears a lot. He is the creator of such airships as the Highwind and Tiny Bronco.

Name: Yuffie Kisaragi
Age: 16
Gender: Female
Weapon: Shuriken
Yuffie is usually the first secret character you encounter. Found in most forests, you can encounter her even before going to Junon for the first time. She was raised in Wutai, where she became a mischievous thief and left Wutai to try and find materia strong enough to save Wutai from the tourism that Shinra had brought. It gets very interesting when she first returns home with Cloud and the group

Name: Vincent Valentine
Age: approx. 60
Gender: Male
Weapon: Pistol
Background info: Very mysterious, the second secret character you find sleeps in Nibelheim. Vincent was a former Turk, and his father Grimoire died and he started courting Lucrecia. He was shot by Hojo and Chaos was inplanted in him. Vincent lay dormant in the ShinRa Manor for 30 years before resurrecting as Vincent/Chaos.
(thanks Hakucho for the info)

Name: Sephiroth
Age: 30
Gender: Male
Weapon: Masamune Blade
Background info: Sephiroth was the main evil guy in Final Fantasy VII. He had certain respect for Cloud but considered him unequal in power. Former First Class Soldier, he turned again ShinRa when discovering he was created experimentally by Hojo. While Lucrecia was pregnant, Hojo injected Jenova cells into her, creating Sephiroth, and giving him the powers he soon comes to acquire.

Name: Rufus
Age: 21
Gender: Male
Weapon: Shotgun
Background info:
Rufus was an arrogant man. The Vice President turned President of Shinra. He had a lot of power, and wished to rule the world with fear. He wanted to find the Promised Land and kill Cloud and Sephiroth along the way. His pet Dark Nation, made a slight appearance but had no real story. Rufus wore a white trench coat, which held his shotgun. He is believed to be dead after Weapon destroys the ShinRa main headquarters, but reappears in a wheelchair in Advent Children.

Name: Elmyra
Age: ?
Gender: Female
Weapon: none
Background info: Aeris' adoptive mother. She resided in Midgar but moved to Kalm later on. She was nice and caring, but she worried about Aeris and didn't want anyone bringing her into danger.

Name: Marlene
Age: 4
Gender: Female
Weapon: none
Background info: Barret's daughter was a shy, young girl. She was Barret's main concern, above saving the planet. She noticed things before anyone else even recognized them. Not much is known about her but she was special in some way.

Name: Zack
Age: 21
Gender: Male
Weapon: Buster Sword
Background info: The 1st class Soldier who befriended Cloud looked almost like Cloud, except with black hair. While in Soldier, he met Aeris and they grew close, but he never returned to Midgar after a special mission to rescue Genesis. His parents in Gongaga hadn't heard from him in 10 years. He wielded the Buster Sword before Cloud took it.

Name: Lucrecia
Age: ?
Gender: Female
Weapon: none
Background Info: Lucrecia was a scientist along side Hojo, and became pregnant with Hojo's child (Sephiroth), who was also implanted with the Jenova cells. She saw what horrors her son would be responsible for as an adult and so after saving Vincent's life by taming Chaos in him with the promateria, she locked herself into the mako-crystal cavern in which Chaos was born. It was because she was incapable of killing herself. She tried that but Jenova wouldn't let it happen and so in order not pose a danger to the world she locked herself into it and became a shadow of her previous self.
(thanks again to Hakucho for the info)


--resources: www.ffshrine.org